JP2000078950A - Retorted boiled rice using container containing oxygen- absorbing agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject food having the same taste as that of a hand- made food product just after cooked, and further having the same taste as that of the hand-made food product without deteriorating the taste even when stored at ordinary temperatures for several months by charging rice and water in a specific heat-resistant container, closing the container and subsequently heating the container at a specific temperature or higher. SOLUTION: This retorted boiled rice is obtained by charging rice and water into a heat-resistant container which can be retorted and whose whole wall surface comprises a multi-layered structure containing an oxygen barrier layer and partially contains an oxygen-absorbing layer disposed on the inside of the oxygen barrier layer, closing the container and subsequently heating the container at >=118 deg.C to retort the cooked rice. Therein, the oxygen-absorbing capacity of the heat-resistant container capable of being retorted under a retorting condition is preferably larger than the total amount of oxygen contained in the rice, the water and the head space in the container, and oxygen is preferably substantially not contained in the head space of the container after retorted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to cooked rice retort foods, and more particularly to a rice cooked rice product having the same taste as a handmade product, and having a reduced taste deterioration even when stored at room temperature for several months. The present invention relates to a method for producing retort food cooked rice having taste.

[0002]

2. Description of the Related Art A method of producing retort-cooked cooked rice is to wash rice (dehydrated) together with water, fill it into a container having heat resistance and light-shielding properties, and to impregnate it with no oxygen, seal it, and then treat it with retort. It is carried out. However, this production method has not been well evaluated because it has a weak smell (rice cooked odor) peculiar to rice such as cooked rice at home and has a stuffy smell-like retort odor. Accordingly, the present applicant has conducted intensive studies on a method for producing cooked rice retort foods having the same taste as handmade products (porridge, etc.). 2-10mg
After adjusting the amount of oxygen in the headspace and the amount of oxygen in the water so as to obtain a retort treatment, a manufacturing method was established, and a patent application was already filed (Japanese Patent Application Laid-Open No. Hei 4-320657).

[0003] As another method for producing cooked cooked rice, retort treatment is performed by filling cooked cooked rice in a heat-resistant and light-shielding container having no oxygen permeability and sealing it. There are methods to do this, but the results are not always good in terms of sensory, despite the additional cooking steps before retort.

[0004]

Although retort foods are generally intended to have a shelf life of several months or more at room temperature unopened, it is known that their taste deteriorates during storage. The same applies to cooked rice and retort food.

[0005] This is described in Japanese Patent Laid-Open No. Hei 4-320657.
The same applies to products obtained by the method for producing cooked rice and retort food according to Japanese Patent Application Publication No. H06-27139. As a result of the time-dependent taste evaluation during storage at room temperature (24 ° C.), the same taste as handmade products immediately after production is obtained. Even if it had, it was recognized that over time, the flavor (off-flavor) different from that of the handmade product, the cooking odor became weak, and the retort odor like the stuffy odor became strong. See Test Example 1 below.

Accordingly, an object of the present invention is to provide a retort food having the same taste as a handmade product immediately after production, and having a reduced taste even after storage at room temperature for several months, and having the same taste as a handmade product. To provide cooked rice.

[0007]

It is said that light, temperature and oxygen are the main causes of deterioration in taste, that is, deterioration of processed foods including retort foods. Many retort foods have a light-shielding property in a container, and conventional retort food cooked rice also has a light-shielding property in a container. Therefore, it is unlikely that the taste deteriorates over time due to light. The lower the storage temperature after retort treatment, the lower the taste can be reduced.However, retort foods such as retort foods such as cooked rice have an advantage in that they can be distributed at room temperature. Storing loses its merits as a room temperature distribution product. In addition, it is impossible to adjust the temperature of the natural environment in summer or winter, and it is difficult to suppress a change in taste over time due to the temperature dependence of a normal-temperature distribution product.

In order to suppress a decrease in taste due to oxygen,
Conventionally, methods such as preventing oxygen permeation of the container and replacing inert gas in the container have been common. JP-A-4-32, cited above
In Japanese Patent No. 0657, retort food cooked rice is cooked and sterilized by retort by adjusting the amount of oxygen in a headspace and the amount of oxygen in water so that the amount of oxygen in a container is 2 to 10 mg per 100 g of raw rice. , It was confirmed that it had the same taste as handmade products (porridge etc.). This is due to the fact that sulfur-containing amino acids in rice grains react with oxygen in the cooking and sterilization process by retort to produce hydrogen sulfide, ammonia, carbonyl compounds, etc. It was considered to have the same taste as handmade products (such as porridge). However, this retort food rice rice container (retort pouch)
Unlike the case of the present invention, the material has no oxygen absorbent layer.

[0009] Japanese Patent Application Laid-Open No. Hei 10-53281 discloses that
"The problem to be solved by the invention" is described as "The degradation of food quality, which was conventionally considered inevitable in molded food packages, is an important step in improving the commercial value of molded food packages and extending the shelf life. The present invention solves this problem and provides a molded food package excellent in long-term preservability without deterioration in flavor and color tone due to trace residual oxygen. And, as a "means for solving the problem", "in view of the above-mentioned problems, a conventional oxygen absorbing resin containing an oxygen absorber is applied to a molded food package in which an oxygen absorber cannot be used, and the packaging is performed. As a result of various studies to remove trace residual oxygen in the body, at least a part of the gas barrier packaging container for storing molded food is composed of an oxygen absorbing resin containing a deoxidizer and absorbs oxygen in the container filled with food. I will do it By the, is that. "Which resulted in the completion of the present invention can solve the above problems. "That is, the present invention, as a means for solving the problem, absorbs oxygen in a container, wherein at least a part of the container is made of a deoxidizing multilayer material having a resin layer in which an oxygen absorbent is mixed with a thermoplastic resin. The molded food packaging body is characterized in that the food is solidified after filling the gas-barrier packaging container with the food in a liquid or semi-liquid flow state and sealing the container. Is a food that is liquid or semi-liquid at the time of filling into a container and solidified according to the shape of the container after filling. " (See paragraphs 4 to 6 in the above publication.)

As for the molded food package according to the present invention, more specifically, "The molded food package of the present invention comprises:
It is formed by filling the barrier container with the food in a liquid or semi-liquid flow state, and then solidifying the food according to the shape of the container. For example, jelly, pudding, bavarois,
Foods such as yokan, kuzu bun, kuzumochi, tofu, sesame tofu, steamed tea bowl, butter, processed cheese, fishery products, rice cakes, etc. are regarded as molded foods. Heating is mainly used for molding these foods. For example, jelly, kneaded yokan, tofu, rice cake and the like are heated and filled in a liquid or semi-liquid flowing state, and then solidified by lowering the temperature after filling. Also,
Steamed yokan, waste products, pudding, fish paste products and the like are filled by utilizing the liquid or semi-liquid state of fluidity at the raw material stage, and after filling, they are heated and solidified to produce a product. In many cases, the present invention utilizes heating for heat sterilization during filling and packaging. Further, in the present invention, when the food package is hermetically sealed, vacuum packaging and inert gas replacement can be used together. (Paragraph 2 of the same gazette)
3) Also, "The oxygen-absorbing multilayer material used in the present invention will be described in detail. The oxygen-absorbing multilayer material is preferably provided with an oxygen-absorbing resin layer obtained by blending an oxygen absorbent with a thermoplastic resin. Uses this oxygen-absorbing resin layer as an intermediate layer,
An outer layer made of a gas barrier material is laminated on the outer side, and an inner layer (sealant layer) composed of a heat sealable resin layer is laminated on the inner side. (Paragraph 24 of the same gazette).

[0011] As can be understood from such a citation, the invention described in Japanese Patent Application Laid-Open No. 10-53281 is a molded food package in which the food package of the present invention needs to be molded. It is completely different from retort food cooked rice that does not. Thus, as a result of the different target foods, the quality of the degraded food which is a problem is different. Therefore, from the description of the above-mentioned publication, it is possible to prevent the quality of the retort food cooked rice according to the present invention from being lowered by the method according to the present invention. It cannot be suggested that it can be done.

[0012] In addition, the containers of the two inventions may overlap in material, but the intended shape is completely different. In the case of molded food packaging, it consists of a molding body and a lid (material) for it, while in the case of retort food cooked rice, retort pouches (pillow pouches, flat pouches, standing pouches, etc.) and ordinary pouches The tray body and the lid (material) for the tray body, and the shape of the container does not have a significant meaning for the content food.

Under the above technical background, and particularly under the background of the technology described in the above-mentioned Japanese Patent Application Laid-Open No. 4-320657, the above-mentioned problem was recognized in addition to the storage temperature after the retort treatment. It was considered that the residual oxygen was not consumed by the reaction in the cooking and sterilization process by the retort.
Accordingly, the present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, by using an oxygen-absorbing agent-containing container that has heat resistance and light-shielding properties and has no oxygen permeability, it is similar to a handmade product immediately after production. The present inventors have found that a retort food cooked rice having a taste similar to that of a handmade product can be obtained even after storage at room temperature for several months, thereby suppressing deterioration of the taste, and completed the present invention.

That is, the present invention provides a retort treatment in which the entire vessel wall has a multilayer structure including an oxygen barrier layer, at least a part of which has a layer containing an oxygen absorbent disposed inside the oxygen barrier layer. The present invention relates to a retort food cooked rice characterized by being retorted after filling rice and water in a possible heat-resistant container and sealing it.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.

In the present invention, the retort food cooked rice is
Rice and porridge. Rice includes not only white rice but also mixed rice such as red rice. In addition, porridge contains brown rice porridge in addition to normal rice porridge, and these are not limited to white porridge (porridge made of only white rice), but also include ingredients such as seasonings, salmon, plums, perilla, eggs, etc. Including things. In the case of porridge, the ratio of rice to water is rice: water =
1: 5 to 8 are preferred.

In the container, the entire surface of the container wall has a multilayer structure including an oxygen barrier layer, at least a part of which has a layer containing an oxygen absorbent disposed inside the oxygen barrier layer and capable of being retorted. There is no particular limitation on the heat-resistant container, that is, a container containing an oxygen absorbent having heat resistance and light-shielding properties and having no oxygen permeability. For example, polypropylene or propylene containing an oxygen absorber containing iron powder as a main component, the entire surface of the vessel wall having a multilayer structure including an oxygen barrier layer, at least a part of which is disposed inside the oxygen barrier layer. Preferred is a heat-resistant container (retort pouch) having a multilayer structure having a layer made of a polypropylene copolymer having a content of 70% or more and a sealant layer made of polypropylene or a polypropylene copolymer having a propylene content of 70% or more. Can be mentioned.

The method of preparing retort food cooked rice using such a retort pouch is disclosed in Japanese Patent Laid-Open No.
The method described in JP-A-320657 can be used.

In addition, when preparing the retort food cooked rice of the present invention, the amount of oxygen that can be absorbed by the retortable heat-resistant container under the retort treatment conditions is determined by the total amount of rice, water and headspace contained in the container. It is preferable that substantially no oxygen is contained in the container headspace after the retort treatment because it is larger than the amount of oxygen, and the total amount of oxygen contained in the water and the headspace is 2 to 10 mg per 100 g of rice. It is preferable to perform retort treatment after adjusting to. Here, “substantially not containing oxygen” indicates that the oxygen concentration is 0.5% or less.

In the retort treatment of cooked cooked rice of the present invention, a high temperature of 118 ° C. or more is considered in consideration of the level of sterilization, the maintenance of food quality as cooking, the effective development of production efficiency and oxygen absorption capacity, and the like. It is preferred to heat with.

As described above, the oxygen absorbent used as a preferable material in the present invention has a multilayer structure including an oxygen barrier layer on the entire surface, at least a part of which is disposed inside the oxygen barrier layer. In a heat-resistant container that can be retorted and has a layer containing, as the material of the resin of the sealant layer and the resin of the layer containing the oxygen absorbent suitable for heating at such a high temperature, there is oxygen permeability and heat resistance Polypropylene having a propylene content or a polypropylene copolymer having a propylene content of 70% or more is preferred. Both may be resins having exactly the same physical properties, or resins having different physical properties may be used.

As the oxygen absorber, any of the conventionally known oxygen absorbers can be used. In particular, iron powder is used as the main agent, and alkali metal halides such as sodium chloride and calcium chloride or alkali earth metal halides are oxidized. What is used as an accelerator is suitable from a viewpoint of hygiene and oxygen absorption capacity.

[0023]

The present invention will be further described with reference to the following examples.

Reference Example 1 (Preparation of Pouch) Pulverization of anhydrous calcium chloride using a vibrating mill in which 20% by weight of granular anhydrous calcium chloride was added to iron powder having an average particle diameter of 10 μm and the inside was replaced with an inert gas. And iron powder were coated to obtain an oxygen absorber. Next, the obtained oxygen absorbent was added to a pent-coated 2
Using an extruder with a shaft, the iron powder content is 20% by weight
The resulting strands were kneaded with polypropylene and then pelletized with a pelletizer to obtain a master batch for forming an oxygen-absorbing layer.

A maleic anhydride-modified polypropylene (10 μm) and an oxygen absorbing layer (30 μm) are co-extruded and laminated between an aluminum foil film and a non-stretched polypropylene film (30 μm), and the aluminum foil side of this laminate contacts the roll surface. Then, the substrate was treated with a 200 ° C. hot roll for 1 second, and then cooled using a 25 ° C. chill roll. Next, a polyethylene terephthalate [PET] film was bonded to an aluminum foil by a dry lamination method using a urethane-based adhesive. Next, the obtained multilayer laminated film was formed into a bag by a bag making machine, thereby producing a retort pouch, which is a heat-resistant container having a layer containing an oxygen absorbent and capable of being retorted and having an oxygen barrier property. The layer configuration is as follows.

PET / aluminum foil / maleic anhydride-modified polypropylene (10 μm) / oxygen absorbing layer (30 μm) /
Polypropylene (30 μm).

Here, in the oxygen-absorbing layer, the masterbatch obtained above is appropriately diluted with polypropylene, so that the iron powder content in the oxygen-absorbing layer is 10%, 5% and 3%, respectively. Were produced (containers 1, 2 and 3).

Further, a maleic anhydride-modified polypropylene (15 μm) was extrusion-laminated between the aluminum foil film and the unstretched polypropylene film (60 μm), and the laminate was placed so that the aluminum foil side of the laminate was in contact with the roll surface.
The substrate was treated with a hot roll at 00 ° C. for 1 second, and then cooled using a chill roll at 25 ° C. Next, the PET film was bonded to an aluminum foil by a dry lamination method using a urethane-based adhesive. Next, the obtained multilayer laminated film was formed into a bag in the same manner as described above, thereby producing a retort pouch which was a heat-resistant container capable of being retorted and not having a layer containing an oxygen absorbent but having an oxygen barrier property (container). 4). The layer configuration is as follows.

PET / aluminum foil / maleic anhydride-modified polypropylene (15 μm) / polypropylene (60 μm)
m).

In each of the containers 1, 2 and 3 having different amounts of iron powder in the oxygen absorbing layer, the pouch was filled with 1 g of water and the head space was filled with 50 cc of air, and the container was sealed. The heating time from start) to 121 ° C is 8 ~
Table 1 below shows the oxygen absorption when the retort treatment was performed for 12 minutes and then at 121 ° C. for 8 minutes.

[0031]

[Table 1]

Example 1 (Production of White Porridge Retort Pouch Food) Next, a 250 g capacity white porridge retort pouch food was produced by the following method. That is, the raw rice was carefully washed three times, then sprinkled naturally for 30 minutes. Since the amount of polished rice absorbed by washing rice increased 1.1 times, the increased weight was adjusted with water. Water was prepared as degassed water so that the dissolved oxygen amount was 0 to 1.0 mg / l.
The thus prepared rice and water were weighed so that rice: water = 1: 8, filled into a container, and hermetically sealed so that the head space was 0 cc. After the hermetic sealing, the end of the container was slightly cut off, and 20 cc of air was injected with a syringe to prevent gas such as air from entering the container, and hermetically sealed again.
For the hermetically sealed product, the heating time from the initial product temperature (start of heating) to 121 ° C. was set to 8 to 12 minutes, and then 8 hours at 121 ° C.
Hold for minutes. As a result, the rice was cooked and cooked moderately, and at the same time, the rice was completely sterilized. After the sterilization was completed, the product was cooled to obtain a retort pouch product.

K is a retort pouch product using a heat-resistant container (container 4) which does not have the above-mentioned layer containing an oxygen absorbent but has oxygen barrier properties and which can be retorted.
In addition, retort pouch products using heat-resistant containers 1 and 2 having oxygen barrier properties and having a layer containing the oxygen absorbent and capable of being retorted were designated as L and M, respectively.
The initial amount of oxygen in each retort pouch product is 6.0-6.0
It was calculated to be 6.2 mg. When the oxygen concentration of the headspace after the retort of L and M was measured, respectively,
0.1% and 0.4%.

The retort pouch products thus obtained were evaluated by comparing L and M with the evaluation items and scale in Table 2 below, using K as a standard. Evaluation panel is 10
Performed by name, strength of rice aroma, taste of rice flavor,
In addition, the standard was set to 0 for the off-flavor and the standard was set to 5 for the overall evaluation.

[0035]

[Table 2]

The results are shown in Table 3 below. The scores in the table are average values of 10 panelists. L and M are
(As shown in Table 1 above, their oxygen absorbable amount under retort treatment conditions was larger than the oxygen amount in the container before the retort treatment.)

[0037]

[Table 3]

In the same manner as described above, a retort pouch product N using a heat-resistant container 3 having an oxygen barrier property and having a layer containing the oxygen absorbent and capable of being retorted was evaluated. The results are also shown in Table 3. The container 3 (as shown in Table 1 above) has a smaller oxygen absorption capacity under retort treatment conditions than the amount of oxygen in the container before the retort, and the superiority of the sensory evaluation of the product N with respect to the product K is slight. Met. The oxygen concentration in the headspace after the retort of N was measured and was 7.2%.

COMPARATIVE EXAMPLE 1 The container 1 was used and the initial product temperature (start of heating) was 112
Temperature to 8 ° C for 12 minutes, then 112 ° C
A white porridge retort pouch food X was produced in the same manner as in Example 1, except that the mixture was heated and cooked and then completely sterilized at the same time. Table 3 also shows the sensory evaluation results of the obtained product X. Considering the level of sterilization, it was difficult to further shorten the time, and it was inferior to L in terms of both sensory and production efficiency.

Comparative Example 2 The same procedure as in Example 1 was carried out except that the rice and water filled in Example 1 were replaced with white porridge cooked using a regular clay pot so that rice: water = 1: 8. The white porridge retort pouch food Y was manufactured by the operation. Table 3 also shows the sensory evaluation results of the obtained product Y. Since a cooking step was involved before the retort treatment, it was inferior to L in terms of both sensory and production efficiency.

Inspection Example 1 (Change over time in quality) A white porridge retort pouch food having a capacity of 250 g was produced by the following method. That is, the raw rice was carefully washed three times, then sprinkled naturally for 30 minutes. Since the amount of polished rice absorbed by washing rice increased 1.1 times, the increased weight was adjusted with water. Water has a dissolved oxygen content of 0
Degassed water was prepared so as to be 1.0 mg / l. The thus prepared rice and water were weighed so that rice: water = 1: 8, filled into a container, and hermetically sealed so that the head space was 0 cc. After the hermetic sealing, the end of the container was slightly cut off, and 3 cc or 7 cc of air was injected with a syringe to prevent gas such as air from entering the container, and the container was hermetically sealed again. 121 ° C from the initial product temperature (start of heating) for hermetically sealed products
The heating time was set to 8 to 12 minutes, and then kept at 121 ° C. for 8 minutes. As a result, the rice was cooked and cooked moderately, and at the same time, the rice was completely sterilized. After the sterilization was completed, the product was cooled to obtain a retort pouch product.

More specifically, a retort pouch product in which 3 cc of air was injected using a conventional container having heat resistance and light-shielding properties and no oxygen permeability (existing container 4) was injected into A, and similarly, 7 cc of air was injected. The prepared retort pouch product was designated as B. In addition, a retort pouch product having heat resistance and light-shielding properties, having no oxygen permeability, and containing 3 cc of air using a container containing oxygen absorbent (existing container 1) was injected with C, and similarly, 7 cc of air. The retort pouch product was designated D. The retort pouch products A and C have an oxygen content of 3.4 to 4.3 mg per 100 g of raw rice, and the retort pouch products B and D have an oxygen content of 7.9 to 8.8 mg per 100 g of raw rice. Was.

Each of the products thus obtained was stored in a constant temperature room at 24 ° C. Storage period is 1 day, 14 days, 3 days after production
0, 60, 90 and 120 days. In order to evaluate the change in taste over time of each stored product on the same day, each product was manufactured on that day. That is, in order to evaluate the taste on the 120th day after the production, the storage period is one day after the production. Manufactured.

The change in taste over time was evaluated according to the evaluation items and scales shown in Table 2 above, with the products of A, B, C, and D as the standard one day after the production of each product of A, B, C, and D. Each storage product was evaluated comparatively. The evaluation panelists performed the evaluation by ten persons. The standard of the standard was 0 for the intensity of the aroma of rice, the preference of the rice flavor, and the off-flavor, and the standard evaluation was 5 points. The results are shown in FIGS. The scores in the figure are the average values of 10 panelists.

In order to confirm the effect of the conventional product on the taste, similarly, according to the evaluation items and scales shown in Table 2 above, each stored product using the conventional container was used as a standard, and the oxygen-absorber-containing container was used as a standard. And the storage products corresponding to the storage periods were compared and evaluated. That is, each stored product of the retort pouch product A is used as a standard, and each stored product of the retort pouch product C is compared and evaluated. Each stored product of the retort pouch product B is used as a standard and each stored product of the retort pouch product D is compared. evaluated. As before, the evaluation panelists performed the evaluation with 10 people, and the standard of the standard was 0 for the intensity of the aroma of the rice, the preference of the rice flavor, and the off-flavor, and the standard evaluation was 5 points. The results are shown in FIGS. The scores in the figure are the average values of 10 panelists.

First, products A and B according to the conventional method will be examined. 1A to 1D show changes in the taste over time of the retort pouch food A, and it is recognized that the taste decreases linearly with time as described above. That is, the aroma of the rice is weak, the flavor of the rice is reduced, and the off-flavor that is not found in the product immediately after production is increased. 2A to 2D show the change in taste of the retort pouch food B over time, and have the same tendency as the change of taste of the retort pouch food A over time. It can be recognized that the retort pouch food B has a larger degree of oxygen per 100 g of rice than the retort pouch food A, and the degree of taste reduction is large.

Next, the products C and D of the present invention will be examined. FIGS. 3A to 3D and FIGS. 4A to 4D show changes in taste over time of retort pouch foods C and D, respectively, from which a tendency different from that of retort pouch foods A and B over time is observed. That is, the taste decreases until the 30th day after the production, but thereafter, the taste tends to be maintained. In addition, the development of an unusual flavor over time was not observed. Retort pouch food D has more oxygen per 100 g of rice than retort pouch food C,
It is recognized that the taste is maintained even if the amount of oxygen is large, and it is considered that the decrease in taste is suppressed more than using a conventional container.

FIGS. 5A to 5D show the results of comparative evaluation of the preserved products of retort pouch foods C and D (products of the present invention) and retort pouch foods A and B (conventional products), respectively. It is recognized that the pouch foods C and D have a stronger aroma of rice than the retort pouch foods A and B, have a favorable rice flavor, and have no off-flavor. That is, it was considered that the product using the oxygen-absorbing agent-containing container had a lower taste reduction during storage than the product using the conventional container, and had the same taste as the handmade product.

Reference Example 2 (Preparation of Retort Container) A master batch for forming an oxygen-absorbing layer prepared by the method described in Reference Example 1 was placed between two unstretched polypropylene films (30 μm) so as to have a thickness of 30 μm. Extrusion lamination was performed to obtain an oxygen-absorbing laminated film for a tray container. On the other hand, ethylene-vinyl alcohol copolymer (EVOH)
Two unstretched polypropylene films (30 μm) were dry-laminated on both sides of the film (30 μm) to obtain an oxygen barrier laminate film for tray containers. Next, polypropylene having a dispersion-filled content of 25% of talc was 600 μm.
The laminate was extrusion-laminated between the oxygen-absorbing laminated film and the oxygen-barrier laminated film so as to have a thickness of, to obtain a laminated sheet for tray containers. The laminated sheet was vacuum-formed so that the oxygen-absorbing laminated film was on the inside of the container to prepare a tray container having a depth of 30 mm and a full capacity of 300 ml and having oxygen absorption and oxygen barrier properties (tray container). 1). The layer configuration is as follows.

Unstretched polypropylene (30 μm) / oxygen absorbing layer (30 μm) / unstretched polypropylene (30 μm)
m) / talc dispersion-filled polypropylene (600 μm) /
Unstretched polypropylene (30 μm) / EVOH (30 μm
m) / Unstretched polypropylene (30 μm).

A tray container having only oxygen barrier properties was prepared in exactly the same manner as in the preparation of the container 5 except that polypropylene alone was used instead of the master batch for forming the oxygen absorbing layer (tray container 2).

The oxygen-barrier laminated film for a tray container obtained in the process of preparing the tray container 1 was prepared so that the master batch for forming the oxygen-absorbing layer prepared by the method described in Reference Example 1 had a thickness of 30 μm. Extrusion lamination was performed between polypropylene films (30 μm) to obtain a laminated film for a tray lid material. The laminated film for a lid material has oxygen absorption and oxygen barrier properties (lid material 1). The layer configuration is as follows.

Unstretched polypropylene (30 μm) / EV
OH (30μm) / Unstretched polypropylene (30μm)
/ Oxygen absorbing layer (30 μm) / Unstretched polypropylene (3
0 μm).

Further, a laminated film for a tray lid material having only an oxygen barrier property was prepared in exactly the same manner as the method of preparing the lid material 1 except that polypropylene alone was used instead of the master batch for forming the oxygen absorbing layer (lid). Material 2).

Tray container 1 containing 200 ml of water and heat-sealed lid material 1, Tray container 2 containing 200 ml of water and heat-sealed lid material 1, Tray container 1 containing water 2
Prepare a heat-sealed lid material 2 containing 00 ml,
A retort heat treatment was performed at 125 ° C. for 10 minutes. Table 4 shows the results of measuring the oxygen concentration in the headspace after the treatment.

[0056]

[Table 4]

Example 2 (Production of retort red rice) Next, 200 g of retort red rice was produced by the following method. That is, 20 g of water was added to 5 g of the asparagus, and the mixture was heated and steamed at 100 ° C. for 20 minutes, and 30 g of water, 140 g of washed and drained glutinous rice, and 0.5 g of salt were added to the tray container 1, and the lid was placed thereon. Cover with wood 1
The tray container and the lid were heat-sealed and sealed while pressing the lid so that the head space was about 20 ml. After sealing, a retort heat treatment was performed at 125 ° C. for 10 minutes to obtain Sekihan P.

In the same manner, the same contents are put in the tray container 2 and the lid member 1, the tray container 1 and the lid member 2, and the tray container 2
Filling, sealing, and retorting were performed for the combination of the lid material 2 and red rice Q, red rice R, and red rice S, respectively. In addition, with respect to the combination of the tray container 2 and the lid member 2, before the lid member 1 was covered, the headspace was almost completely replaced with the nitrogen gas by flowing nitrogen gas, and the headspace was sealed and retorted to obtain a red rice T. .

The thus-obtained retort red rice was compared and evaluated using the evaluation items shown in Table 2 and the scale using red rice T as a standard. The evaluation panelists performed by 10 persons.

The results are shown in Table 5 below. The scores in the table are average values of 10 panelists. Good results were obtained in the order of red rice P, red rice R, red rice Q, red rice T and red rice S.

[0061]

[Table 5]

After storing red rice P, red rice Q, red rice R, red rice S, and red rice T for one year at room temperature and in a dark place, panel 1 was prepared in exactly the same manner using newly manufactured red rice T as a standard.
Evaluation by 0 people was performed. The results are shown in Table 6 below. The scores in the table are average values of 10 panelists.
Sekihan P, Sekihan R, New T, Sekihan Q, Sekihan T and Sekihan S
In this order, good results were obtained.

[0063]

[Table 6]

Rice cooked and sealed in a container having oxygen absorption and oxygen barrier properties according to the present invention and subjected to a retort heat treatment is not only compared with the case where an oxygen barrier container is used, but also when filled and sealed. Compared with the nitrogen gas replacement, the rice has a strong aroma, the flavor of the rice is preferable, there is no off-flavor, and even after long-term storage, it is similar to a new one,
It was shown to retain flavor.

[0065]

According to the present invention, a hand-made product can be prepared by a simple method of adjusting the amount of oxygen in a container, using a container containing an oxygen absorbent which has heat resistance and light shielding properties and does not transmit oxygen. It has the same taste as that of the above, has a reduced taste even when stored at room temperature for several months, has a good flavor with high commercial value, and does not disintegrate the rice surface as when using a pot. Cooked retort food rice can be easily obtained.

[Brief description of the drawings]

FIG. 1A shows a temporal change in quality of a conventional product A (inspection example 1).

FIG. 1B shows a temporal change in quality of a conventional product A (inspection example 1).

FIG. 1C shows a temporal change in quality of a conventional product A (inspection example 1).

FIG. 1D shows a temporal change in quality of a conventional product A (inspection example 1).

FIG. 2A shows a temporal change in quality of a conventional product B (inspection example 1).

FIG. 2B shows a temporal change in the quality of the conventional product B (inspection example 1).

FIG. 2C shows a temporal change in quality of the conventional product B (inspection example 1).

FIG. 2D shows a temporal change in the quality of conventional product B (inspection example 1).

FIG. 3A shows a temporal change in the quality of the product C of the present invention (inspection example 1).

FIG. 3B shows a temporal change in quality of the product C of the present invention (inspection example 1).

FIG. 3C shows a temporal change in quality of the product C of the present invention (inspection example 1).

FIG. 3D shows a temporal change in the quality of the product C of the present invention (inspection example 1).

FIG. 4A shows the change over time in the quality of the product D of the present invention (inspection example 1).

FIG. 4B shows a temporal change in quality of the product D of the present invention (inspection example 1).

FIG. 4C shows the change over time in the quality of the product D of the present invention (inspection example 1).

FIG. 4D shows a change over time in the quality of the product D of the present invention (inspection example 1).

FIG. 5A shows a comparison of changes over time between a product of the present invention (C and D) and a conventional product (A and B) (Test Example 1).

FIG. 5B shows a comparison of the change over time between the product of the present invention (C and D) and the conventional product (A and B) (Test Example 1).

FIG. 5C shows a comparison of changes over time between a product of the present invention (C and D) and a conventional product (A and B) (Test Example 1).

FIG. 5D shows a comparison of changes over time between the product of the present invention (C and D) and the conventional product (A and B) (Test Example 1).

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Tomomi Hayashi 2-12-1, Shimonoge, Takatsu-ku, Kawasaki City, Kanagawa Prefecture Inside Knorr Foods Co., Ltd. (72) Wakaba Murakami 2--12 Shimonoge, Takatsu-ku, Kawasaki City, Kanagawa Prefecture No. 1 Inside Knorr Foods Co., Ltd. (72) Norio Matsumoto 2-12-1, Shimonoge, Takatsu-ku, Kawasaki, Kanagawa Prefecture Inside Knorr Foods Co., Ltd. (72) Yoshihiro Kobayashi 1-1-1, Suzukicho, Kawasaki-ku, Kawasaki-shi, Kanagawa No. Ajinomoto Co., Ltd.

Claims (5)

[Claims] 1. A retort-processable heat-resistant material having a multilayer structure including an oxygen barrier layer on the entire wall surface of a container, at least a part of which has a layer containing an oxygen absorbent disposed inside the oxygen barrier layer. After filling the container with rice and water and sealing,
Retort food cooked rice, which is heated to 118 ° C. or more and retorted. 2. The retort-treatable heat-resistant container according to claim 1, wherein the amount of oxygen that can be absorbed under retort treatment conditions is rice,
The retort food cooked rice according to claim 1, wherein the amount of oxygen is larger than the total amount of oxygen contained in water and the headspace, and substantially no oxygen is contained in the container headspace after the retort treatment. 3. A heat-resistant container capable of being retorted, wherein the entire surface of the container wall has a multilayer structure including an oxygen barrier layer, and at least a part of the container has an iron powder disposed inside the oxygen barrier layer. Multilayer structure having a layer comprising polypropylene or a polypropylene copolymer having a propylene content of 70% or more containing an oxygen absorber as a main component and a sealant layer comprising a polypropylene or a polypropylene copolymer having a propylene content of 70% or more The retort food cooked rice according to claim 1 or 2, wherein the cooked rice is a heat-resistant container. 4. The retort food cooked rice according to claim 1, wherein the ratio of rice to water is 1: 5 or more. 5. The retort food cooked rice according to claim 4, wherein the total amount of oxygen contained in water and headspace is adjusted to 2 to 10 mg per 100 g of rice and then retorted.